All About Mammograms: Section 2.a.

CONTENTS

2.1 Introduction: What is a Mammogram?
2.2 Screening Mammography
2.3 Special Populations and Breast Screening
2.3.1 Pregnant Women
2.3.2 Postmenopausal Women Taking Hormone Replacement Therapy (HRT)
2.3.3 Women with Breast Implants
2.3.4 Women with Prior Breast Biopsy or Surgery
2.3.5 Women with Post-Mastectomy Breast Reconstruction
2.3.6 Men

Forward to 2B on mammography. Back to 1C on Risk and breast density.

Sometimes I question my sanity, sometimes it replies.

The diagnostic or investigational procedure that underpins the breast screening program worldwide is X-ray mammography.

Breast cancer screening programs using mammography also create clinical and research data.

But, if there are abnormalities on initial screening, additional testing, using other screening methods, may be necessary.

Also, there are remarkable refinements to further imaging techniques in recent years.

Have you ever had a mammogram Gretchen?

Not a screening one because I’m still a bit young, thank you.

I have, I found a tiny lump, it turned out to be nothing at all.

2.1 Introduction: What is a Mammogram?

When a woman first receives an invitation to attend for a routine screening mammogram, it can be a cause for concern.

If you have never had a mammogram, the questions are, what is a mammogram and what does it involve?

Furthermore, there is a lot of helpful information on the internet that can help prepare you for your mammogram. Check out our whole section on Breast Screening

Some patients may worry about the radiation dose from a routine screening mammogram. However, this dose is equivalent only to natural ‘background’ radiation over about three months.

Women who have BRCA1 or BRCA2 gene mutations may be at slightly greater risk for radiation-induced breast changes.

I’ve heard your boob’s are squashed flat as pancakes during a mammogram!

Did someone say pancakes? Yes, please can we go and get pancakes?

‘I can’t wait for my mammogram,’ said no woman EVER, but it really wasn’t too bad.

Figure 2.1

Diagram of the patient experience of mammography.
(Courtesy A.D.A.M. online image bank).

2.2 Screening Mammography

A mammogram is an X-ray image of the breast. Differences in breast tissue appear as different shades of grey on the image. Fat, being relatively radiolucent, permitting passage of the X-rays, appears as black on the film.

Tumors will appear as shades of grey while calcifications (micro-calcifications) are white.

Hmmmmm, ‘shades of grey’ now, where have I heard that before?

Grey, it’s a dull color, I really don’t see what all the fuss is about.

Figure 2.2 Cranio-caudal (CC) Mammogram.
The normal breast.

(Courtesy of Yale.edu.imaging).

What is a Mammogram and Benign Breast Lesions

Benign breast lesions usually show, regular contours. Suspicious tumors, on the other hand, often appear as spiculated masses (needle-like shapes).

In addition, pleomorphic micro-calcifications, with or without a mass or lump, are likely to be mammographic cancers in 30% to 50% of cases.

On average, a mammogram will show around 85% of the breast content. So, up to 15% of breast tissue will not show on a mammogram.

Therefore, 15% of breast cancers may not show on the scan. However, it is possible to detect micro-calcifications on a mammogram that are typical of malignant tissue.

What are pleomorphic micro-calcifications?

Micro-calcifications are small calcium deposits that appear as white specks. So, ‘pleomorphic’ is a term that refers to micro-calcifications of varying sizes and shapes.

Mammogram Screening: What is a Mammogram?

Research shows that Screening mammography consistently decreases breast cancer-related deaths.

Routine evaluation of the breast involves obtaining two views, craniocaudal (CC) and mediolateral oblique (MLO) of each breast.

The density of the breasts is important too. an increase in breast density increases the risk of breast cancer. Furthermore, this can also decrease the ability of the mammogram to detect small lesions.

Confucious he say, ‘war not determine who right. War determine who left’.

What is a Mammogram and Breast Implants

Women who have breast implants still need routine mammogram screening to evaluate any remaining breast tissue.

Women with breast implants who have no underlying breast tissue do not require regular mammograms.

The standard imaging technique in women with breast implants involves four views, rather than the usual two views per breast.

What is sensitivity? Because people always say that I don’t have any.

No Hector, in statistics sensitivity measures the percentage of sick people who are correctly identified as having the condition by mammogram.

Just over 84 percent then, not bad.

Mammograms can detect early-stage breast cancer.

This is the case even when there are no symptoms of breast cancer.

The United States surveillance data examined more than 1.8 million mammograms. These mammograms were taken between 2004 and 2008 on women between the ages of 18 years and 80 years.

The results show that mammography has a sensitivity of 84.4 % and a specificity of 90.8 %.

Furthermore, the recall rate was 9.6 %, and positive predictive value was 4.3 %. So this means that 4.3% of recall patients had a breast cancer diagnosis.

I’ve found when people say you’re overly sensitive, it’s usually because they are overly annoying!

In 2014, a long-term, 25-year follow-up study raises the question of a possible decrease in the impact of screening mammography.

This is probably due to the fact that the treatment for breast cancer is more effective (Miller et al., 2014).

2.3 Special Populations and Breast Screening

There are certain groups who deserve special consideration for mammographic breast screening.

2.3.1 Pregnant Women

As a rule, specialists do not routinely perform mammograms in pregnant women.

Usually, doctors will perform a mammogram in pregnancy to diagnose and evaluate a suspected cancer. They may also check the other breast or assess findings that are not clear on ultrasound.

The breast undergoes physiological changes during pregnancy and lactation. Because of this, new breast disorders in pregnancy are usually benign and secondary to hormonal changes.

However, breast cancer in pregnancy represents up to 3 % of all breast cancers, and these tend to have a poorer prognosis.

The poorer prognosis of breast cancer in pregnancy is usually due to a delay in diagnosis because of difficulties in obtaining or interpreting mammograms.

In addition, clinical examinations can pose a problem too due to natural changes in the breasts in pregnancy.

It must be so difficult to find out you have breast cancer whilst pregnant. How sad.

Yes. There are some very good support groups around so check out local ones and get together with women who are in the same boat!

There are some very large international groups as well for the more politically minded.

The possible effect of radiation on the fetus means that mammography should be avoided during pregnancy.

The developing fetus is most susceptible to effects from radiation in the first few weeks of gestation.

In general, radiation doses of more than 5 rads or 50 mGy are harmful. A four view standard mammogram with abdominal shielding exposes the fetus to 0.4 rads or 4 mGy.

Breast imaging of a pregnant woman with a palpable breast abnormality begins with an ultrasound.

So mammography is only necessary if the ultrasound findings are suspicious for malignancy.

Pregnancy and menopause in the same post…Next mood swing in 6 minutes. Be Afraid….Be Very Afraid.

2.3.2 Postmenopausal Women Taking Hormone Replacement Therapy (HRT)

The normal changes of the breast tissue with age are inhibited by the use of hormone replacement therapy (HRT),

So, HRT increases breast density and may also decrease the sensitivity of mammography. The false-positive re-call rate may increase in post-menopausal women taking HRT.

2.3.3 Women with Breast Implants

Breast implants are huge, and not just literally. Indeed, statistics estimate that over two million women have breast implants in the U.S. alone.

Furthermore, the majority of breast implants consist of an envelope full of either silicone gel or saline.

If there are two million breast implants, does that mean that one million women have two implants each?

No Hector, and that right there is why you should not be on this site!

Hey, don’t be so sexist, men get breast cancer too.

Women with implants require routine screening mammograms to evaluate the leftover breast tissue.

Women with breast implants and no remaining breast tissue do not usually undergo routine mammography.

The presence of breast implants makes mammography very difficult. The implant contents are radiopaque, and this obscures small breast lesions.

In addition, the presence of the implant makes it difficult to evaluate all parts of the breast; it also makes compression difficult.

Standard imaging technique in women with breast implants involves four views, rather than the usual two views per breast.

Positioning is important to include as much breast tissue as possible by pushing the implant out of view. Usually, a Standard CC and MLO projection of each breast are necessary, both of which include the implant. Next, the implant is displaced back against the chest wall, with the breast tissue pulled forward and the two views are re-taken by mammogram.

Once again we did not schedule this month’s Apathetic Anonymous Meeting.

2.3.4 Women with Prior Breast Biopsy or Surgery

In the United States, around 1% to 2% of women have a breast biopsy following mammographic screenings. However, other countries have a much lower rate than this.

The effect of a prior breast biopsy on subsequent mammographic interpretation was investigated in a review of data from the Breast Cancer Surveillance Consortium. This study involved over 2 million mammograms in nearly 800,000 women (Taplin et al., 2010).

Okay, here we go. Specificity, what is that? Be specific!

Specificity measures the percentage of healthy people correctly identified as not having the disease.

If a woman has a prior breast biopsy for a benign breast condition, this can reduce specificity for a breast cancer diagnosis in subsequent screening mammograms and biopsies.

Sometimes, this is because of the suspicious characteristics of the breast tissue and/or differing thresholds of mammogram interpretation for a prior biopsy.

So simply, if a woman has had a previous biopsy she is more at risk in the future of having a false positive result again.

2.3.5 Women with Post-Mastectomy Breast Reconstruction

Following a breast mastectomy, a mammogram is not routinely necessary. Because there is no breast tissue left, mammography provides no additional benefit in detecting recurrence.

Several methods of breast reconstruction are available following mastectomy. So, if silicone implants are present, MRI evaluation for breast implant issues is more sensitive than mammography.

Surgeons can also transfer tissue from other parts of the body, typically muscle to the skin, in reconstruction surgery.

A transverse rectus abdominis myo-cutaneous (TRAM) flap consists of muscle and fatty tissue from the abdominal wall that is moved up to the chest. This tissue has an intact blood supply to create the breast mound. Similar reconstruction can also be performed using the latissimus dorsi muscle.

Being screened again after already having gone through treatment and reconstruction must be tough.

Studies have shown that breast reconstruction does not increase the risk of cancer recurrence or make it harder to check with mammography.

Well that’s really good news then.

More Breast Reconstructions and Mammograms

More commonly, surgeons construct a deep inferior epigastric perforator (DIEP) flap.

The flap consists of abdominal fat with its native blood supply.

Identifying breast cancer recurrences in the reconstructed flap is important as it has implications for future.

At present, a physical examination is a method of choice in monitoring myo-cutaneous breast reconstructions. However, it is difficult to identify lesions that are deep and can be difficult to distinguish a palpable area of fat necrosis from recurrent cancer.

Both mammography and ultrasound of a reconstructed breast are technically feasible. The mammographic appearance of recurrence is similar to that seen in a native breast.

Specific features on mammography can help distinguish recurrence from benign post-operative fat necrosis as a cause of a palpable breast lump

Never go out with a baker. They’re too kneady.

Ultrasound with fine-needle aspiration (FNA) or core biopsy has been shown to be valuable in identifying recurrence in both clinically palpable and occult lesions.

There is contradictory evidence regarding routine imaging of asymptomatic women with TRAM flap breast reconstruction.

Consciousness: That annoying time between naps.

2.3.6 Men

Although male breast cancer is uncommon, studies show the incidence rate is increasing (Giordano, 2004).

The American Cancer Society estimates that 2,190 men developed breast cancer in 2012 with 410 breast cancer deaths. This accounts for less than 1% of total breast cancer diagnoses. (Siegel, 2011).

Men do not undergo routine screening mammography.

Medics will refer men for imaging when clinical findings are present, such as a breast lump, breast thickening or pain.

The initial male mammogram includes standard bilateral CC and MLO views. Use of narrower paddles may facilitate compression, depending on breast size. Similar to women, additional mammographic views and ultrasound may be indicated to characterize any abnormalities and to facilitate biopsy if indicated.

Is Google a woman? Because it won’t let you finish your sentence without coming up with other suggestions.

Patient Information:

American Cancer Society. Breast Cancer Prevention and Early Detection: Mammograms. (Retrieved February 3^rd 2015)

Centers for Disease Control and Prevention. What screening tests are there (Retrieved February 6^th 2015): http://www.cancer.org/cancer/breastcancerinmen/detailedguide/breast-cancer-in-men-what-is-breast-cancer-in-men

More patient information for this section is on this page.

References:

Miller, A.B., Wall, C., Baines, C.J., Sun, P., To, T., Narod, S.A. (2014). Twenty five year follow-up for breast cancer incidence and mortality of the Canadian National Breast Screening Study: randomised screening trial. BMJ 348, g366. (Retrieved October 29^th 2014): https://www.ncbi.nlm.nih.gov/pubmed/24519768

Taplin, S.H., Abraham, L., Geller, B.M., Yankaskas, B.C., Buist, D.S., Smith-Bindman, R., Lehman, C., Weaver, D., Carney, P.A., Barlow, W.E. (2010). Effect of previous benign breast biopsy on the interpretive performance of subsequent screening mammography. J Natl Cancer Inst. 102(14), 1040. (Retrieved October 28^th 2014): https://www.ncbi.nlm.nih.gov/pubmed/20601590

More references for this section are on this page.